It had an Officers' Club aboard, housing a large table of oak, which was heavily scored with numerous gouges and scorches from cigars set upon its surface. There was also a bar stocked with a number of varieties of liquor. It also housed s gold-fringed blue UNSC flag, photographs of past officers and captains of the Gettysburg, and a tin Civil War daguerreotype that displayed battlefields of charging men, cavalry and cannons.

Eventually, John-117, along with several survivors of Battle of Installation 04 and Fall of Reach, used the Gettysburg, fusing it with the Covenant ship Ascendant Justice, thus becoming the first human-Covenant hybrid vessel in history.[4] It was used because the Ascendant Justice could not do the two Slipspace jumps in and out of a group of Covenant ships fast enough using just its own reactor. [5]

Gettysburg is named after the Battle of Gettysburg, the American Civil War battle that took place on July 1-3 1863, in Gettysburg, Pennsylvania, on Earth. This is interesting, in that it was fused with a Covenant vessel, just as the two factions of the American Civil War eventually rejoined into one country.